She's his handler. Just like royal children needed minders whenever they went in public, to keep them from picking their noses or doing something unseemly, so VJ has to keep an eye on the self-indulgent child occupying the office of the President. She really blew it with selfie-gate, and I think this photo shows her over-compensating for the error.
She is his Governess.... his Au Pair?
How did Reggie fit into this entourage? Every road trip is a Reggie-Barry play date, making Valerie's job all the harder.
BTW, Barry was really yucking it up at this supposedly serious occasion. LOL isn't really an option at funerals, is it?